This invention relates to contact lens manufacturing and the lenses made thereby, and in particular to contact lenses with marks thereon indicating the lenses are samples, and a method of manufacturing lenses with indicator markings.
Colored contact lenses have been a commercial success. Acceptance by consumers has been so great that many variations of lenses and processes for making such lenses have been devised and patented. Examples of patents in this field include U.S. Pat No. 4,582,402, U.S. Pat. No. 5,720,188, U.S. Pat. No. 5,414,477, and U.S. Pat. No. 5,936,705. These patents disclose articles of manufacture and methods of making such contact lenses. Success has gone beyond colored lenses and now extends to lenses with several colors and designs beyond mere color.
The desirability and novelty of these items has led to difficulty in controlling the distribution of samples. In particular, the sample items are sometimes sold or diverted, rather than being used as samples for the customer. Samples are typically distributed in order to allow customers or potential customers to view the cosmetic effect before they purchase the lenses. In addition, the customer may have the opportunity to view several colors or designs before making a choice. However, there are several ways for the lenses to fall into misuse. Sample lenses may be sold to a customer, rather than used as samples. The lenses may be diverted to another seller, who may not be an authorized customer of the contact lens manufacturer, and who may violate the manufacturer""s selling, support and safety requirements.
The lenses may be diverted to a seller who sells them for a price lower than the manufacturer""s authorized sellers. The lenses may be illegally diverted into the hands of someone who dispenses the lens without a prescription. The lenses may be illegally smuggled into another country where the lenses are not approved by the appropriate health authorities. These latter concerns are highly important since they affect legal liability and public health.
Many solutions have been attempted to solve these problems. Marking the packages with sample indicators has not solved the problem. Warnings that sharing of contact lenses may lead to the spread of microorganisms have not helped. The problem of the unauthorized use of sample lenses will only become greater, as more varieties of lenses, colors and designs become available. In addition, while there is a greater problem with colored lenses, the problem is also applicable to non-colored lenses, that is, lenses that are clear rather than colored. What is needed is a contact lens that will discourage the widespread unauthorized distribution and use of samples, but which samples will still function for their intended purpose, that is, of allowing a customer or potential customer to sample the lenses.
In one aspect the invention is a contact lens on which a sample indicator is imprinted. The sample indicator may comprise the word or words xe2x80x9cDemoxe2x80x9d, xe2x80x9cSamplexe2x80x9d, xe2x80x9cModelxe2x80x9d, xe2x80x9cNot for Salexe2x80x9d, or xe2x80x9cDemonstration Onlyxe2x80x9d. The advantage of such sample lenses is that the lens itself is fully functional for all purposes of a sample lens, except for ordinary daily wear. The sample lens may not be suitable for that purpose, because the sample indicator may well be conspicuous to another person viewing the eyes of the wearer of the sample lens. In particular, most colored contact lenses are colored in the area of the lens superimposed on the iris of the wearer""s eye. The sample indicator is therefore most conspicuous when it is imprinted in the lens periphery, that is, the area between the outer edge of the lens and the area superimposed on the iris of the wearer""s eye. This is applicable to both colored and non-colored lenses.
At the same time, this placement of the sample indicator has very few disadvantages. No marking is required in the area of the lens superimposed over the pupil of the eye, assuring no visual interference with the wearer. The indicator is visible when the lens is not being worn, and, depending on the color of the indicator, may be more or less conspicuous while being worn. In other words, the color may contrast with that of a lens, or a user""s iris, or the color of the indicator may be more compatible with that of the lens. The manufacturer can continue to supply sample lenses, confident they will not be diverted, and thus a wearer may sample several lens colors or styles to determine the cosmetic effect of the lens. In terms of manufacture, the sample indicator may be imprinted in an existing step in a color-printing process, or the sample indicator may be imprinted in a separate step. The color and formulation of the inks used to imprint the sample indicator will likely determine how many steps of printing are required.